Dry Falls of the Columbia

The geological history of the Grand Coulee of Eastern Washington discloses that about 10,000 years ago a series of glacial ice plugs damming a huge lake, near what is now Missoula, MT, periodicaly broke loose and created walls of water 300 feet high cascading over these 400 foot high basalt cliffs making the largest waterfall ever known on earth. Each release continued downstream gouging out huge depressions in the layered basalt of this Grand Coulee Canyon for another 60 miles forming many lakes, some of which are shown, namely Dry Falls, Deep, Perch, Sun Lakes, Blue and Lenore. It has been estimated the flows of water equalled what would be many times the combined flows of all the rivers in the world today. For more precise viewing, suggest you look under Photo Sizes and choose either Large or Original.